Siemens



(No Model.)

v G. W. VON SIEMENS. GONVERTER SYSTEM FOR ELECTRIC BAILWAYS.

Patentd Aug L/i T14 INVENTORI ATTORNEY UNITED STATES PATENT Crrrcn.

GEORG WILHELM VON SIEMENS, OF BERLIN, GERMANY, ASSIGNOR TO SIEMENSHALSKE, OF SAMEPLACE.

CONVERTER SYSTEM FOR ELECTRIC RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 502,538, dated August1, 1893.

Application filed March 29, 1893. Serial No. 468,176- (No model.)Patented in Austria-Hungary August 7, 1886, Nos. 31,923 and 2,522 andNos. 570,681 and 2,394, and in England August 26,1886,No. 10,926.

To all whom it may concern:

Be it known that I, GEORG WILHELM VON SIEMENS, a subject of the Emperorof Germany, residing at the city of Berlin, in the German Empire, haveinvented new and useful Improvements in Electric Railways, (for which Ihave obtained Letters Patent as follows: in England, No. 10,926, datedAugust 26, 1886; in Austria-Hungary, Nos. 31,923 and 2,522 and Nos.570,681 and 2,394, dated August 7, 1886,) of which the following is aspecification.

The use of transformers, or secondary generators for transmittingelectrical energy, offers the advantage that a much higher tension maybe employed than is possible with transmission by continuous current, sothat considerable energy can be transmitted through great distancesbymeans of comparatively small conductors, while at the same time theregulation of the power of the motor is capable of being effected muchmore easily.

For the purposes of this invention, any known construction of alternatecurrent machine is employed for generating the current, while for themotor to be driven by the current, there is employed a dynamo machinethat can produce continuous currents.

In applying this invention to electric railways, in which the motors onthe carriages receive the current from the traffic rails, or fromconductors extending alongside of said rails, the transformers areemployed as follows: Transformers are placed at certain distances apartalong the line of tramc rails, the primary coils receiving the currentfrom the generator being arranged either in parallel are or in serieswith the conductors therefrom, or each having a separate circuit, whilethe terminals of the secondary coils are connected respectively to thetwo traffic rails, when these are used as the conductors, or to theseparate working conductors, when these are employed. The traffic rails,or the working conductors may be continuous and fed from all of thetransformers, or divided into sections, and each section fed from onetransformer; or, on the carriage may be placed a transformer whoseprimary coils are con- 5 nected in the well known manner, throughternate current machine, the tension at the terminals of the primarycoils would then be always constant.

In the accompanying diagrams which illustrate my invention,-similarnumerals of reference indicate like parts.

Figure 1 shows a number of transformers coupled in parallel between thefeeder conductors from the generator and the working conductors of thesystem. Fig. 2 shows a number of transformers with their primary coilsin series with the feeder conductor from the generator, and theirsecondary coils connected to separate sections of the workingconductors. Fig. 3 shows the transformers arranged in separate feedingcircuits from the generator. Fig. 4 shows a carriage, on which aremounted a motor, a transformer having its primary coil in parallelthrough movable contacts with the feeder conductors from the generator,and a current modifying coil in the primary; and further, shows themotor connected to the secondary coil of the transformer.

In the diagrams, 10 represents any suitable generator of alternatingcurrents; 11, the feeder conductors from and to the generator. In Fig.4, these conductors serve as the working conductors.

12 are the working conductors. These conductors may consist of the railsof atramway, or of one rail and a conductor placed parallel thereto, orthere may be separate, distinct conductors placed above, below, orotherwise disposed relatively to the rails upon which the vehicle moves.divided into sections, as desired.

13 is a transformer of the usual type having primary and secondary coils14: and 15.

In Fig. 1, the transformers are shown cou- 100 They may be continuous orpled in parallel between the feeder conductors 11 and the workingconductors 12; that is to say, the primary coils of the transformers areconnected to the conductors 11, and the secondary coils 15 to theconductors 12.

In Fig. 2, the transformers 13 are arranged in series. All the primarycoils are in series with the conductors 11, while the secondary coilsare each connected by itself to a single section of the workingconductors 12.

In Fig. 8, the primary coils of the separate transformers are fedthrough separate feeder conductors 11, while the secondary coils areconnected in parallel arc with the continuous conductors 12.

In each of the arrangements shown, the transformers are separated at adistance from each other along the line of the road. This distance willdepend upon the character of the currents transmitted, length of theroad, &c.

In Fig. 4, the arrangement is somewhat differentinstead of a number oftransformers arranged along the line of the road, a single transformer13 is placed upon the vehicle. In this case, the primary coil 14 of thetransformer is connected to sliding or rolling contacts 16, which bearrespectively, one, for instance, upon one of the feeder conductors 11and the other upon the other of the feeder conductors, or upon a railsuitably connected to one of the feeder conductors. The secondary coil15 has its terminals connected to the motor 17. 18 is a switch forbreaking the circuit between the secondary of the transformer and themotor. This switch can be arranged in a manner well understood, toreverse the current through the motor. Any suitable type of motor may beused, 1'. a, one adapted to be worked with alternating currents, whichmay be an alternating motor, or a machine which, when used as a dynamo,will generate constant currents; that is to say, a machine of theSiemens or Gramme type, having its field magnets sub-divided by makingthem of laminated plates.

In the arrangement shown in Figs. 1 and 3, where the secondaries of thetransformers are in parallel with the feeder conductors, all of saidtransformers will be active at the same time, and each one will do workin proportion to the resistance of its secondary circuit. OW- ing,however, to the motion of the carriage, this resistance will varyaccording to the distance of the carriage from the particulartransformer from which it is receiving current. The difference ofpotential at the terminals of the secondary coils will have to be takencomparatively low, having regard to the difficulty of effecting aperfect insulation of the traiiic rails, or separate conductors whichdistribute current.

The above described system,as all other systems for the transmission ofenergy for a similar purpose-requires that a regulating device he usedto determine the speed of the carriage, 8:0. For this purpose I make useof the following device:

19, Fig. 4, diagrammatically represents a wire coil or bobbin providedwith a movable iron core. For electrical reasons, which are readilyunderstood, if the iron core is introduced into the bobbin, a counterelectro-mo tive force to that traversing the primary of the transformerwill be induced, and will therefore cut down the current in the primary.Instead of using this device, various other well known means formodifying the current transmitted to the motor on the vehicle may beemployed.

I do not limit myself to the use of any particular kind of contacts, asany suitable means may be employed for putting the eleotro-motor ormotors on the Vehicles in operative re lation with the source of energy.

I make no claim in this application to the employment, in an electricrailway system of the character described, of a transformer located 011the Vehicle, as this feature has been made the subject of a companionapplication Serial No. 468,177, filed March 29, 1893.

Having thus described my invention, I claim 1. In an electric railway, asource of alternating currents, a moving vehicle upon a line of railway,a motor mounted upon said vehicle to propel the same, an inductionaltransformer interposed between the generator and motor for modifying thecurrent from the generator, and means for supplying energy from thegenerator to the motor, substantially as described.

2. In an electric railway, a source of alternating currents, conductorsextending from said source, a number of moving vehicles upon a line ofrailway, motors mounted on said vehicles to propel the same, and anumber of current modifying inductional transformers connected to saidconductors and interposed between the generator and the motors formodifying the current supply from the generator to the motors.

3. In an electric railway, the combination of an alternating generator,a vehicle or vehicles moving along a track, a motor or motors mountedupon said vehicle or vehicles, an inductional transformer ortransformers interposed between the generator and the motors forchanging. the tension of the current from the generator, and means forregulating the supply of energy to the motors.

4. In an electric railway, the combination of an alternating generator,a moving vehicle or vehicles upon a line of railway, a motor or motorsmounted upon said vehicle or vehicles, inductional devices for changingthe tension of a current interposed between the generator and themotors, and connections composed wholly or in part of the rails forcarrying the current from the tension changing devices to the motors.

5. In an electric railway, a source of alternating currents, feederconductors extending therefrom, a number of transformers distributedalong the way having their primary coils electrically connected withsaid feeder conductors, working conductors'also extending along the wayand electrically connected with the secondary coils of saidtransformers, a vehicle or vehicles upon the said line of railway, anelectric motor or motors on said vehicle or vehicles, and means forsupplying current from the working conductors to the motor or motors insuch a way as to energize said motor or motors and cause them to propelthe vehicle or vehicles.

6. In an electric railway, an alternating generator, feeder conductorsextending therefrom, a number of transformers distributed along the wayand connected to the feeder conductors in parallel arc, workingconductors extending along the way and electrically connected with thesecondary coils of the transformers, a vehicle or vehicles on the saidline of railway, and electric motor or motors on said vehicle orvehicles which receive energy from the working conductors in such a wayas to be energized by the current from said working conductors.

7. In an electric railway, a source of alternating currents, feederconductors extending therefrom, a series of transformers distributedalong the way and having their primary coils electrically connected withsaid feeder conductors, working conductors also extending along the wayand electrically connected with the secondary coils of saidtransformers, a vehicle, and an electro motor on said vehicle throughwhich an alternating current is transmitted, in operative relation withsaid working conductors.

8. In an electric railway, a source of alternating currents, feederconductors extending therefrom, a series of transformers distributedalong the way and having their primary coils electrically connected withsaid feeder conductors, sectional working conductors also extendingalong the way and electrically connected with the secondary coils ofsaid transformers, a vehicle, and an electro motor on said vehiclethrough which an alternating current is transmitted, in operativerelation with the section of the working conductors over which it istravelin 9. In an electric railway, a source of alternating currents,feeder conductors extending therefrom, a series of transformersdistributed along the way and having their primary coils electricallyconnected in parallel arc with said feeder conductors, workingconductors also extending along the way and electrically connected withthe secondary coils of said transformers, a vehicle, and anelectro-motor on said vehicle, through which .an alternating current istransmitted, in operative relation with said working conductors.

10. In an electric railway, a source of alternating currents, feederconductors extending ing current is transmitted, andatransformerinterposed between said feeder conductors and said electro motor and inoperative relation therewith.

11. In an electric railway, a source of alternating currents, feederconductors extending therefrom, a vehicle having an electro motormounted thereon, through which an alternating current is transmitted, atransformer interposed between said feeder conductors and said electromotor, and in operative relation therewith, and means for modifying thecurrent transmitted through the electro motor.

12. In an electric railway, a source of alternating currents, feederconductors extending therefrom, a vehicle having an electro motormounted thereon, through which an alternating current is transmitted, atransformer interposed between said feeder conductors and said electromotor, and in operative relation therewith, and means carried by thevehicle for varying the current transmitted-through the motor.

13. In an electric railway, the combination with a generator ofalternating currents, a vehicle having a propelling electro motormounted thereon, through which an alternating current is transmitted,and a current transformer having a primary and a secondary coil, saidprimary coil in operative relation with said generator, and saidsecondary coil in operative relation with said electro motor.

14. In an electric railway, the combination with a generator ofalternating currents, a vehicle having a propelling electro motormounted thereon, through which an alternating current is transmitted, atcurrent transformer having a primary and a secondary coil, said primarycoil in operative relation with said generator, and said secondary coilin operative relation with said electro motor, and means for modifyingthe current transmitted through the motor.

15. In a system of electrical distribution, a source of alternatingcurrents, feeder conductors extending therefrom, a series oftransformers distributed along said feeder conductors and having theirprimary coils electrically connected thereto, sectional workingconductors having each separate section con nected with the secondarycoil of one transformer, and translating devices in said section throughwhich an alternating current is transmitted.

In testimony whereof I affix my signature in the presence of twowitnesses.

GEORG WILIIELM VON SIEMENS.

Witn esses:

GUSTAV STARZEL, MAX WAGNER.

IEO

